Doppler Shift Estimate Reporting with Pre-Compensation

ABSTRACT

A first cellular base station transmits a configuration message to a reporting device installed on a high-speed vehicle. The configuration message specifies one or more parameters of a Doppler measurement report. The reporting device performs one or more first Doppler measurements on the first base station and/or one or more second Doppler measurements on a second base station. The reporting device transmits the Doppler measurement report to the first and/or second base stations. The Doppler measurement report may be used by the first and/or second base stations to perform Doppler pre-compensation on transmissions to the reporting device.

FIELD

The present application relates to wireless communications, and moreparticularly to systems, apparatuses, and methods for providing Dopplershift information in a cellular communication system.

DESCRIPTION OF THE RELATED ART

Wireless communication systems are rapidly growing in usage. In recentyears, wireless devices such as smart phones and tablet computers havebecome increasingly sophisticated. In addition to supporting telephonecalls, many mobile devices (i.e., user equipment devices or UEs) nowprovide access to the internet, email, text messaging, and navigationusing the global positioning system (GPS), and are capable of operatingsophisticated applications that utilize these functionalities.Additionally, there exist numerous different wireless communicationtechnologies and standards. Some examples of wireless communicationstandards include GSM, UMTS (associated with, for example, WCDMA orTD-SCDMA air interfaces), LTE, LTE Advanced (LTE-A), NR, HSPA, 3GPP2CDMA2000 (e.g., 1×RTT, 1×EV-DO, HRPD, eHRPD), IEEE 802.11 (WLAN orWi-Fi), BLUETOOTH™, etc.

Effectively performing cellular communications may be complicated byDoppler shift in a high-mobility scenario such as cellularcommunications on a high-speed train (HST). In some deployments, thenetwork may pre-compensate for the Doppler shift experienced by arapidly moving UE. However, the network may not be aware of the degreeof Doppler shift to be pre-compensated. Accordingly, improvements in thefield are desired.

SUMMARY

Embodiments are presented herein of apparatuses, systems, and methodsfor a reporting device to transmit a Doppler measurement report to acellular base station. The reporting device may be a cellulartransceiver installed on a high-speed vehicle, and the cellular basestation may be a 5G NR gNB, in some embodiments.

In some embodiments, the reporting device receives a configurationmessage from a first base station specifying one or more parameters of aDoppler measurement report.

In some embodiments, the reporting device performs one or more firstDoppler measurements on the first base station and/or one or more secondDoppler measurements on a second base station. The Doppler measurementsmeasure a Doppler shift experienced by transmissions between thereporting device and the base stations.

In some embodiments, the reporting device transmits the Dopplermeasurement report to the first and/or second base stations, where theDoppler measurement report is based on the one or more first Dopplermeasurements and the one or more parameters. The Doppler measurementreport may specify a differential between Doppler shifts of the firstand second base stations. The Doppler measurement report may be used bythe first and/or second base stations to perform Dopplerpre-compensation on transmissions to the reporting device.

Note that the techniques described herein may be implemented in and/orused with a number of different types of devices, including but notlimited to base stations, access points, cellular phones, portable mediaplayers, tablet computers, wearable devices, and various other computingdevices.

This Summary is intended to provide a brief overview of some of thesubject matter described in this document. Accordingly, it will beappreciated that the above-described features are merely examples andshould not be construed to narrow the scope or spirit of the subjectmatter described herein in any way. Other features, aspects, andadvantages of the subject matter described herein will become apparentfrom the following Detailed Description, Figures, and Claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an exemplary (and simplified) wireless communicationsystem, according to some embodiments;

FIG. 2 illustrates an exemplary base station in communication with anexemplary wireless user equipment (UE) device, according to someembodiments;

FIG. 3 illustrates an exemplary block diagram of a UE, according to someembodiments;

FIG. 4 illustrates an exemplary block diagram of a base station,according to some embodiments;

FIG. 5 is a schematic illustration of a high-speed train moving betweentwo base stations, where the base stations perform pre-compensation toremove a Doppler shift, according to some embodiments;

FIG. 6 is a flowchart diagram illustrating a method for a reportingdevice to provide a Doppler measurement report to one or more basestations responsive to receiving a configuration message, according tosome embodiments;

FIG. 7 is a flowchart diagram illustrating a method for a reportingdevice to autonomously provide a Doppler measurement report to one ormore base stations, according to some embodiments;

FIG. 8 illustrates an example message format for a CSI-Reportinginformation element (IE), according to some embodiments;

FIG. 9 illustrates an example message format for aCSI-AssociatedReportConfigInfo IE, according to some embodiments;

FIG. 10 illustrates an example message format for a reportQuantity IE,according to some embodiments; and

FIGS. 11A and 11B are tables illustrating low and high latencyrequirements, respectively, for channel state information (CSI)reporting, according to some embodiments.

While features described herein are susceptible to various modificationsand alternative forms, specific embodiments thereof are shown by way ofexample in the drawings and are herein described in detail. It should beunderstood, however, that the drawings and detailed description theretoare not intended to be limiting to the particular form disclosed, but onthe contrary, the intention is to cover all modifications, equivalentsand alternatives falling within the spirit and scope of the subjectmatter as defined by the appended claims.

DETAILED DESCRIPTION Acronyms

Various acronyms are used throughout the present disclosure. Definitionsof the most prominently used acronyms that may appear throughout thepresent disclosure are provided below:

-   -   UE: User Equipment    -   RF: Radio Frequency    -   BS: Base Station    -   GSM: Global System for Mobile Communication    -   UMTS: Universal Mobile Telecommunication System    -   LTE: Long Term Evolution    -   NR: New Radio    -   TX: Transmission/Transmit    -   RX: Reception/Receive    -   MIMO: Multiple Input Multiple Output    -   RAT: Radio Access Technology    -   TRS: Tracking Reference Signal

Terms

The following is a glossary of terms that may appear in the presentdisclosure:

Memory Medium—Any of various types of non-transitory memory devices orstorage devices. The term “memory medium” is intended to include aninstallation medium, e.g., a CD-ROM, floppy disks, or tape device; acomputer system memory or random access memory such as DRAM, DDR RAM,SRAM, EDO RAM, Rambus RAM, etc.; a non-volatile memory such as a Flash,magnetic media, e.g., a hard drive, or optical storage; registers, orother similar types of memory elements, etc. The memory medium maycomprise other types of non-transitory memory as well or combinationsthereof. In addition, the memory medium may be located in a firstcomputer system in which the programs are executed, or may be located ina second different computer system which connects to the first computersystem over a network, such as the Internet. In the latter instance, thesecond computer system may provide program instructions to the firstcomputer system for execution. The term “memory medium” may include twoor more memory mediums which may reside in different locations, e.g., indifferent computer systems that are connected over a network. The memorymedium may store program instructions (e.g., embodied as computerprograms) that may be executed by one or more processors.

Carrier Medium—a memory medium as described above, as well as a physicaltransmission medium, such as a bus, network, and/or other physicaltransmission medium that conveys signals such as electrical,electromagnetic, or digital signals.

Computer System (or Computer)—any of various types of computing orprocessing systems, including a personal computer system (PC), mainframecomputer system, workstation, network appliance, Internet appliance,personal digital assistant (PDA), television system, grid computingsystem, or other device or combinations of devices. In general, the term“computer system” may be broadly defined to encompass any device (orcombination of devices) having at least one processor that executesinstructions from a memory medium.

User Equipment (UE) (or “UE Device”)—any of various types of computersystems or devices that are mobile or portable and that perform wirelesscommunications. Examples of UE devices include mobile telephones orsmart phones (e.g., iPhone™, Android™-based phones), tablet computers(e.g., iPad™, Samsung Galaxy™), portable gaming devices (e.g., NintendoDS™, PlayStation Portable™, Gameboy Advance™, iPhone™), wearable devices(e.g., smart watch, smart glasses), laptops, PDAs, portable Internetdevices, music players, data storage devices, or other handheld devices,etc. In general, the term “UE” or “UE device” can be broadly defined toencompass any electronic, computing, and/or telecommunications device(or combination of devices) which is easily transported by a user andcapable of wireless communication.

Wireless Device—any of various types of computer systems or devices thatperform wireless communications. A wireless device can be portable (ormobile) or may be stationary or fixed at a certain location. A UE is anexample of a wireless device.

Communication Device—any of various types of computer systems or devicesthat perform communications, where the communications can be wired orwireless. A communication device can be portable (or mobile) or may bestationary or fixed at a certain location. A wireless device is anexample of a communication device. A UE is another example of acommunication device.

Base Station (BS)—The term “Base Station” has the full breadth of itsordinary meaning, and at least includes a wireless communication stationinstalled at a fixed location and used to communicate as part of awireless telephone system or radio system.

Processing Element (or Processor)—refers to various elements orcombinations of elements that are capable of performing a function in adevice, e.g. in a user equipment device or in a cellular network device.Processing elements may include, for example: processors and associatedmemory, portions or circuits of individual processor cores, entireprocessor cores, processor arrays, circuits such as an ASIC (ApplicationSpecific Integrated Circuit), programmable hardware elements such as afield programmable gate array (FPGA), as well any of variouscombinations of the above.

Wi-Fi—The term “Wi-Fi” has the full breadth of its ordinary meaning, andat least includes a wireless communication network or RAT that isserviced by wireless LAN (WLAN) access points and which providesconnectivity through these access points to the Internet. Most modernWi-Fi networks (or WLAN networks) are based on IEEE 802.11 standards andare marketed under the name “Wi-Fi”. A Wi-Fi (WLAN) network is differentfrom a cellular network.

Automatically—refers to an action or operation performed by a computersystem (e.g., software executed by the computer system) or device (e.g.,circuitry, programmable hardware elements, ASICs, etc.), without userinput directly specifying or performing the action or operation. Thusthe term “automatically” is in contrast to an operation being manuallyperformed or specified by the user, where the user provides input todirectly perform the operation. An automatic procedure may be initiatedby input provided by the user, but the subsequent actions that areperformed “automatically” are not specified by the user, i.e., are notperformed “manually”, where the user specifies each action to perform.For example, a user filling out an electronic form by selecting eachfield and providing input specifying information (e.g., by typinginformation, selecting check boxes, radio selections, etc.) is fillingout the form manually, even though the computer system must update theform in response to the user actions. The form may be automaticallyfilled out by the computer system where the computer system (e.g.,software executing on the computer system) analyzes the fields of theform and fills in the form without any user input specifying the answersto the fields. As indicated above, the user may invoke the automaticfilling of the form, but is not involved in the actual filling of theform (e.g., the user is not manually specifying answers to fields butrather they are being automatically completed). The presentspecification provides various examples of operations beingautomatically performed in response to actions the user has taken.

Configured to—Various components may be described as “configured to”perform a task or tasks. In such contexts, “configured to” is a broadrecitation generally meaning “having structure that” performs the taskor tasks during operation. As such, the component can be configured toperform the task even when the component is not currently performingthat task (e.g., a set of electrical conductors may be configured toelectrically connect a module to another module, even when the twomodules are not connected). In some contexts, “configured to” may be abroad recitation of structure generally meaning “having circuitry that”performs the task or tasks during operation. As such, the component canbe configured to perform the task even when the component is notcurrently on. In general, the circuitry that forms the structurecorresponding to “configured to” may include hardware circuits.

Various components may be described as performing a task or tasks, forconvenience in the description. Such descriptions should be interpretedas including the phrase “configured to.” Reciting a component that isconfigured to perform one or more tasks is expressly intended not toinvoke 35 U.S.C. § 112, paragraph six, interpretation for thatcomponent.

FIGS. 1 and 2—Exemplary Communication System

FIG. 1 illustrates an exemplary (and simplified) wireless communicationsystem in which aspects of this disclosure may be implemented, accordingto some embodiments. It is noted that the system of FIG. 1 is merely oneexample of a possible system, and embodiments may be implemented in anyof various systems, as desired.

As shown, the exemplary wireless communication system includes a basestation 102 which communicates over a transmission medium with one ormore (e.g., an arbitrary number of) user devices 106A, 106B, etc.through 106N. Each of the user devices may be referred to herein as a“user equipment” (UE) or UE device. Thus, the user devices 106 arereferred to as UEs or UE devices.

The base station 102 may be a base transceiver station (BTS) or cellsite, and may include hardware and/or software that enables wirelesscommunication with the UEs 106A through 106N. If the base station 102 isimplemented in the context of LTE, it may alternately be referred to asan ‘eNodeB’ or ‘eNB’. If the base station 102 is implemented in thecontext of 5G NR, it may alternately be referred to as a ‘gNodeB’ or‘gNB’. The base station 102 may also be equipped to communicate with anetwork 100 (e.g., a core network of a cellular service provider, atelecommunication network such as a public switched telephone network(PSTN), and/or the Internet, among various possibilities). Thus, thebase station 102 may facilitate communication among the user devicesand/or between the user devices and the network 100. The communicationarea (or coverage area) of the base station may be referred to as a“cell.” As also used herein, from the perspective of UEs, a base stationmay sometimes be considered as representing the network insofar asuplink and downlink communications of the UE are concerned. Thus, a UEcommunicating with one or more base stations in the network may also beinterpreted as the UE communicating with the network.

The base station 102 and the user devices may be configured tocommunicate over the transmission medium using any of various radioaccess technologies (RATs), also referred to as wireless communicationtechnologies, or telecommunication standards, such as GSM, UMTS (WCDMA),LTE, LTE-Advanced (LTE-A), LAA/LTE-U, 5GNR, 3GPP2 CDMA2000 (e.g., 1×RTT,1×EV-DO, HRPD, eHRPD), Wi-Fi, etc.

Base station 102 and other similar base stations operating according tothe same or a different cellular communication standard may thus beprovided as one or more networks of cells, which may provide continuousor nearly continuous overlapping service to UE 106 and similar devicesover a geographic area via one or more cellular communication standards.

Note that a UE 106 may be capable of communicating using multiplewireless communication standards. For example, a UE 106 might beconfigured to communicate using either or both of a 3GPP cellularcommunication standard or a 3GPP2 cellular communication standard. Insome embodiments, the UE 106 may be configured to perform grouped MIMOcommunications such as according to the various methods describedherein. The UE 106 might also or alternatively be configured tocommunicate using WLAN, BLUETOOTH™, one or more global navigationalsatellite systems (GNSS, e.g., GPS or GLONASS), one and/or more mobiletelevision broadcasting standards (e.g., ATSC-M/H), etc. Othercombinations of wireless communication standards (including more thantwo wireless communication standards) are also possible.

FIG. 2 illustrates an exemplary user equipment 106 (e.g., one of thedevices 106A through 106N) in communication with the base station 102,according to some embodiments. The UE 106 may be a device with wirelessnetwork connectivity such as a mobile phone, a hand-held device, awearable device, a computer or a tablet, or virtually any type ofwireless device. The UE 106 may include a processor (processing element)that is configured to execute program instructions stored in memory. TheUE 106 may perform any of the method embodiments described herein byexecuting such stored instructions. Alternatively, or in addition, theUE 106 may include a programmable hardware element such as an FPGA(field-programmable gate array), an integrated circuit, and/or any ofvarious other possible hardware components that are configured toperform (e.g., individually or in combination) any of the methodembodiments described herein, or any portion of any of the methodembodiments described herein. The UE 106 may be configured tocommunicate using any of multiple wireless communication protocols. Forexample, the UE 106 may be configured to communicate using two or moreof CDMA2000, LTE, LTE-A, 5G NR, WLAN, or GNSS. Other combinations ofwireless communication standards are also possible.

The UE 106 may include one or more antennas for communicating using oneor more wireless communication protocols according to one or more RATstandards. In some embodiments, the UE 106 may share one or more partsof a receive chain and/or transmit chain between multiple wirelesscommunication standards. The shared radio may include a single antenna,or may include multiple antennas (e.g., for MIMO) for performingwireless communications. In general, a radio may include any combinationof a baseband processor, analog RF signal processing circuitry (e.g.,including filters, mixers, oscillators, amplifiers, etc.), or digitalprocessing circuitry (e.g., for digital modulation as well as otherdigital processing). Similarly, the radio may implement one or morereceive and transmit chains using the aforementioned hardware.

In some embodiments, the UE 106 may include separate transmit and/orreceive chains (e.g., including separate antennas and other radiocomponents) for each wireless communication protocol with which it isconfigured to communicate. As a further possibility, the UE 106 mayinclude one or more radios that are shared between multiple wirelesscommunication protocols, and one or more radios that are usedexclusively by a single wireless communication protocol. For example,the UE 106 may include a shared radio for communicating using either ofLTE or CDMA2000 1×RTT (or LTE or NR, or LTE or GSM), and separate radiosfor communicating using each of Wi-Fi and BLUETOOTH™. Otherconfigurations are also possible.

In a cellular communication system, a wireless device may be served by acellular base station according to a cellular link, such as a cellularlink established according to LTE, LTE-A, or 5G NR. For example, awireless device may establish a session with an AMF entity of thecellular network by way of a gNB that provides radio access to thecellular network. Alternatively, or in addition, the cellular networkmay operate according to another cellular communication technology(e.g., LTE, UMTS, CDMA2000, GSM, etc.), according to variousembodiments.

Establishing the wireless link may include establishing a RRC connectionwith the serving cellular base station, at least according to someembodiments. Establishing the RRC connection may include configuringvarious parameters for communication between the wireless device and thecellular base station, establishing context information for the wirelessdevice, and/or any of various other possible features, e.g., relating toestablishing an air interface for the wireless device to performcellular communication with a cellular network associated with thecellular base station. After establishing the RRC connection, thewireless device may operate in a RRC connected state, in which thecellular base station may perform downlink data communications with thewireless device, among other possible types of communication.

FIG. 3—Block Diagram of an Exemplary UE Device

FIG. 3 illustrates a block diagram of an exemplary UE 106, according tosome embodiments. As shown, the UE 106 may include a system on chip(SOC) 300, which may include portions for various purposes. For example,as shown, the SOC 300 may include processor(s) 302 which may executeprogram instructions for the UE 106 and display circuitry 304 which mayperform graphics processing and provide display signals to the display360. The processor(s) 302 may also be coupled to memory management unit(MMU) 340, which may be configured to receive addresses from theprocessor(s) 302 and translate those addresses to locations in memory(e.g., memory 306, read only memory (ROM) 350, NAND flash memory 310)and/or to other circuits or devices, such as the display circuitry 304,radio 330, connectorI/F 320, and/or display 360. The MMU 340 may beconfigured to perform memory protection and page table translation orset up. In some embodiments, the MMU 340 may be included as a portion ofthe processor(s) 302.

As shown, the SOC 300 may be coupled to various other circuits of the UE106. For example, the UE 106 may include various types of memory (e.g.,including NAND flash 310), a connector interface 320 (e.g., for couplingto a computer system, dock, charging station, etc.), the display 360,and wireless communication circuitry 330 (e.g., for LTE, LTE-A, NR,CDMA2000, BLUETOOTH™, Wi-Fi, GPS, etc.). The UE device 106 may includeat least one antenna (e.g. 335 a), and possibly multiple antennas (e.g.illustrated by antennas 335 a and 335 b), for performing wirelesscommunication with base stations and/or other devices. Antennas 335 aand 335 b are shown by way of example, and UE device 106 may includefewer or more antennas. Overall, the one or more antennas arecollectively referred to as antenna 335. For example, the UE device 106may use antenna 335 to perform the wireless communication with the aidof radio circuitry 330. As noted above, the UE may be configured tocommunicate wirelessly using multiple wireless communication standardsin some embodiments.

The UE 106 may include hardware and software components for implementingmethods for the UE 106 to perform grouped MIMO communications such asdescribed further subsequently herein. The processor(s) 302 of the UEdevice 106 may be configured to implement part or all of the methodsdescribed herein, e.g., by executing program instructions stored on amemory medium (e.g., a non-transitory computer-readable memory medium).In other embodiments, processor(s) 302 may be configured as aprogrammable hardware element, such as an FPGA (Field Programmable GateArray), or as an ASIC (Application Specific Integrated Circuit).Furthermore, processor(s) 302 may be coupled to and/or may interoperatewith other components as shown in FIG. 3 , to perform grouped MIMOcommunications according to various embodiments disclosed herein.Processor(s) 302 may also implement various other applications and/orend-user applications running on UE 106.

In some embodiments, radio 330 may include separate controllersdedicated to controlling communications for various respective RATstandards. For example, as shown in FIG. 3 , radio 330 may include aWi-Fi controller 352, a cellular controller (e.g. for LTE, LTE-A, NR,etc.) 354, and BLUETOOTH™ controller 356, and in at least someembodiments, one or more or all of these controllers may be implementedas respective integrated circuits (ICs or chips, for short) incommunication with each other and with SOC 300 (and more specificallywith processor(s) 302). For example, Wi-Fi controller 352 maycommunicate with cellular controller 354 over a cell-ISM link or WCIinterface, and/or BLUETOOTH′ controller 356 may communicate withcellular controller 354 over a cell-ISM link, etc. While three separatecontrollers are illustrated within radio 330, other embodiments havefewer or more similar controllers for various different RATs that may beimplemented in UE device 106.

Further, embodiments in which controllers may implement functionalityassociated with multiple radio access technologies are also envisioned.For example, according to some embodiments, the cellular controller 354may, in addition to hardware and/or software components for performingcellular communication, include hardware and/or software components forperforming one or more activities associated with Wi-Fi, such as Wi-Fipreamble detection, and/or generation and transmission of Wi-Fi physicallayer preamble signals.

In some embodiments, the UE 106 may be configured within (e.g., as partof) a high-speed vehicle such as a high-speed train, an airplane, aboat, or another type of vehicle, to provide cellular access to otherdevices and/or systems within the vehicle.

FIG. 4—Block Diagram of an Exemplary Base Station

FIG. 4 illustrates a block diagram of an exemplary base station 102,according to some embodiments. It is noted that the base station of FIG.4 is merely one example of a possible base station. As shown, the basestation 102 may include processor(s) 404 which may execute programinstructions for the base station 102. The processor(s) 404 may also becoupled to memory management unit (MMU) 440, which may be configured toreceive addresses from the processor(s) 404 and translate thoseaddresses to locations in memory (e.g., memory 460 and read only memory(ROM) 450) or to other circuits or devices.

The base station 102 may include at least one network port 470. Thenetwork port 470 may be configured to couple to a telephone network andprovide a plurality of devices, such as UE devices 106, access to thetelephone network as described above in FIGS. 1 and 2 . The network port470 (or an additional network port) may also or alternatively beconfigured to couple to a cellular network, e.g., a core network of acellular service provider. The core network may provide mobility relatedservices and/or other services to a plurality of devices, such as UEdevices 106. In some cases, the network port 470 may couple to atelephone network via the core network, and/or the core network mayprovide a telephone network (e.g., among other UE devices serviced bythe cellular service provider).

The base station 102 may include at least one antenna 434, and possiblymultiple antennas (e.g., to support grouped MIMO communications such asdescribed further subsequently herein). The antenna(s) 434 may beconfigured to operate as a wireless transceiver and may be furtherconfigured to communicate with UE devices 106 via radio 430. Theantenna(s) 434 communicates with the radio 430 via communication chain432. Communication chain 432 may be a receive chain, a transmit chain orboth. The radio 430 may be designed to communicate via various wirelesstelecommunication standards, including, but not limited to, NR, LTE,LTE-A, WCDMA, CDMA2000, etc. The processor 404 of the base station 102may be configured to implement and/or support implementation of part orall of the methods described herein, e.g., by executing programinstructions stored on a memory medium (e.g., a non-transitorycomputer-readable memory medium). Alternatively, the processor 404 maybe configured as a programmable hardware element, such as an FPGA (FieldProgrammable Gate Array), or as an ASIC (Application Specific IntegratedCircuit), or a combination thereof. In the case of certain RATs, forexample Wi-Fi, base station 102 may be designed as an access point (AP),in which case network port 470 may be implemented to provide access to awide area network and/or local area network (s), e.g. it may include atleast one Ethernet port, and radio 430 may be designed to communicateaccording to the Wi-Fi standard. The base station 102 may operateaccording to the various methods as disclosed herein for performinggrouped MIMO communications in a cellular communication system.

High Speed Mobility Scenarios

In some embodiments, a UE or another type of device may conduct cellularcommunications in a high-speed mobility scenario such as a high-speedtrain (e.g., a magnetic levitation (Maglev) train), an airplane, or aboat, among other possibilities. In these embodiments, it may bedesirable to correct for a Doppler shift experienced by a high-speed UEcommunicating with a stationary base station.

For example, as shown in FIG. 5 , a high-speed train (HST) configured toconduct cellular communications may travel between two base stations andmay experience a very high positive Doppler shift from one BS and a veryhigh negative Doppler shift from the other BS. As results, the compositechannel may vary quickly, close to or more than 2 kHz. This variationmay reduce the channel capability and/or make it challenging for thewireless device to perform accurate channel estimation.

To address these and other concerns, different deployments may allow theUE to estimate two separate Doppler shifts, one from each BS, to assistUE channel estimation. Alternatively, the network (NW) maypre-compensate for the Doppler shift, where the network applies afrequency shift to its transmissions to the UE that is equal inmagnitude but opposite in sign to the Doppler shift. To facilitateDoppler shift pre-compensation, the UE may inform the NW of the Dopplershift that the UE is experiencing. The NW may estimate the Doppler shiftbased on UE uplink (UL transmissions), e.g., SRS, DMRS, etc.Alternatively, the NW may estimate Doppler shift based on explicitreporting from the UE. Embodiments herein present methods and devicesfor a high-mobility UE to utilize either a) channel state information(CSI)-ReportConfig messaging orb) media access control-control element(MAC-CE) messaging to report Doppler shift estimates to the NW.

FIGS. 6-7—Doppler Measurement Reporting

FIGS. 6-7 are flowchart diagrams illustrating methods for a wirelessdevice to perform Doppler measurement reporting to a cellular basestation, according to some embodiments. Aspects of the methods of FIGS.6-7 may be implemented by wireless devices, such as a UE 106 or anothertype of device and a BS 102 illustrated in and described with respect tovarious of the Figures herein, or more generally in conjunction with anyof the computer circuitry, systems, devices, elements, or componentsshown in the above Figures, among other devices, as desired. Forexample, a processor (and/or other hardware) of such a device may beconfigured to cause the device to perform any combination of theillustrated method elements and/or other method elements. In someembodiments, a high-speed vehicle (e.g., a high-speed train, boat orairplane) may have installed thereon a cellular transceiver configuredto communicate with one or more base stations (e.g., gNBs). The cellulartransceiver may be configured to provide cellular access to otherdevices in the vehicle (i.e., smart phones, tablets, laptops, etc.)through a wireless local area network. In general, the device that isperforming and reporting the Doppler shift measurements may be variouslyreferred to as a “reporting device”, a “device”, a “wireless device”, ora “UE”. In some embodiments, the methods described in FIGS. 6-7 may beperformed by the cellular transceiver installed in the vehicle.Alternatively or additionally, individual UE devices within the vehiclemay be configured to perform the described method steps. Note that whileat least some elements of the methods of FIG. 6 are described in amanner relating to the use of communication techniques and/or featuresassociated with LTE, LTE-A, NR, and/or 3GPP specification documents,such description is not intended to be limiting to the disclosure, andaspects of the methods of FIGS. 6-7 may be used in any suitable wirelesscommunication system, as desired. The methods described in FIGS. 6 and 7are similar in some respects, but differ in that FIG. 6 describes amethod whereby the device receives configuration information from a basestation prior to performing Doppler measurement reporting, whereas FIG.7 describes a method where the device autonomously performs Dopplermeasurement reporting.

In various embodiments, some of the elements of the methods shown may beperformed concurrently, in a different order than shown, may besubstituted for by other method elements, or may be omitted. Additionalmethod elements may also be performed as desired. As shown, the methodof FIG. 6 may operate as follows.

At 602, a configuration message is received from a first base station.The configuration message specifies one or more parameters of a Dopplermeasurement report. In some embodiments, the configuration message is achannel state information (CSI)-ReportConfig message, and the Dopplermeasurement report is included within a CSI transmission. The one ormore parameters may include an instruction for the device to perform aplurality of Doppler measurements on the first base station and reportan average over the plurality of Doppler measurements. This instructionmay be included in a resourcesForChannelMeasurement information element(IE) of a CSI-ReportConfig message, in some embodiments. The one or moreparameters may additionally instruct the device to perform and reportDoppler shift measurements on a second base station. For example, adevice on a high-speed train may be moving between and may be currentlyin communication range of two base stations, and the configurationmessage may instruct the device to measure the Doppler shift of bothbase stations.

The parameters may additionally or alternatively include a specificationof one or more time and frequency resources for transmitting the Dopplermeasurement report.

In some embodiments, the one or more parameters may include a minimumabsolute reportable Doppler shift, a maximum absolute reportable Dopplershift and a quantization step size. The minimum and maximum absolutereportable Doppler shift specify the minimum and maximum values that thedevice is permitted to report (e.g., 0 Hz and 8000 Hz, or another pairof values), and the quantization step size (e.g., 100 Hz) specifies theresolution for reporting the Doppler shift (i.e., the device may roundits Doppler measurement to the nearest step, for example, a measuredDoppler shift of 813 Hz may be rounded to and reported as 800 Hz for astep size of 100 Hz).

At 604, Doppler measurements are performed. The Doppler measurements mayinclude one or more first Doppler measurements performed on the firstbase station. The Doppler measurements measure the Doppler shift onmessaging between the device and the first base station. The one or morefirst Doppler measurements may be performed responsive to receiving theconfiguration message. The one or more Doppler measurements may includea plurality of Doppler measurements on the first base station, and theDoppler measurement report may specify an average of the plurality ofDoppler measurements.

The Doppler measurements may further include one or more second Dopplermeasurements on a second base station. The first base station may be areceding base station relative to the device, while the second basestation is approaching, or vice versa. The Doppler measurement reportmay be further based on the one or more second Doppler measurements. Invarious embodiments, the Doppler measurement report may report adifferential of the first and second Doppler measurements, or it mayindividually report the first and second Doppler measurements. In someembodiments, the device may transmit a first Doppler measurement to thefirst base station that includes the first Doppler measurement results,and a second Doppler measurement to the second base station thatincludes the second Doppler measurement results. Alternatively, thedevice may transmit the same Doppler measurement report to both thefirst and second base stations, and the Doppler measurement report mayinclude both the first and second Doppler measurement results (or it mayspecify only the differential between the first and second Dopplermeasurement results).

Depending on the velocity of the reporting device and the relativelocations of the first base station, the second base station and thereporting device, the Doppler shifts of the first and second basestations may be similar in magnitude and opposite in sign. For example,if the velocity of the reporting device and the locations of the firstbase station, the second base station, and the reporting device are allcolinear, the Doppler shifts of the first and second base stations willbe substantially identical in magnitude (for example, if the reportingdevice is moving in a straight line directly away from the first basestation and directly toward the second base station, the Doppler shiftsof the base stations will be equal in magnitude and opposite in sign).In some circumstances, the locations of the two base stations and thereporting device may deviate slightly from collinearity (e.g., when ahigh-speed train is travelling in a straight line away from the firstbase station and toward the second base station, and the base stationsare miles apart and several hundred feet away from the train tracks). Inthese situations, the Doppler shifts of the first and second basestations will differ in magnitude by an amount that increases, forexample, as one base station's location is moved farther away from thetrain tracks. For CSI Doppler measurement reporting, reporting adifferential between two Doppler measurements utilizes fewer networkresources than reporting each Doppler measurement individually. In someembodiments, the base stations may instruct the reporting device toreport the differential measurement, thus reducing the network load, andeach base station may assume its Doppler shift is equal to half of thedifferential measurement (thus incurring a slight error, depending onthe deviation from collinearity). The first and second base stations mayeach implement pre-compensation on transmissions to the reporting devicewith opposite signs and a common magnitude equal to half thedifferential. Alternatively, in some embodiments, the first (or second)base station may implement pre-compensation with the full differentialand the other base station may not implement pre-compensation. In theseembodiments, the differential Doppler shift between the two basestations may be substantially removed or reduced, even though anabsolute Doppler shift for the two base stations may persist. Reportingthe differential Doppler shift between the two base stations may bedesirable when the deviation from collinearity of the base stations andthe reporting device is sufficiently small. Alternatively, fordeployments with significant deviations from linearity, it may bedesirable for the base stations to instruct the UE to individuallyreport each of the two Doppler shift measurements to the two basestations.

At 606, the Doppler measurement report is transmitted to the first basestation. The Doppler measurement report is based at least on the one ormore first Doppler measurements and the one or more parameters. Forexample, the Doppler measurement report may be constructed by thereporting device according to the one or more parameters. The Dopplermeasurement report may additionally be transmitted to one or more otherbase stations, or each base station may receive a distinct Dopplermeasurement report. The Doppler measurement report may be includedwithin a CSI message. The Doppler measurement report may be used by thefirst and/or second base stations to perform pre-compensation of theirrespective Doppler shifts, as shown in FIG. 5 , so that the devicereceives signals from the base stations without a Doppler shift (or witha substantially reduced Doppler shift). For example, the device mayreceive communications from the first and/or second base stations thathave been Doppler pre-compensated based on the Doppler measurementreport.

In some embodiments, the Doppler measurement report specifies that theDoppler measurement report is invalid. For example, if the measuredDoppler shift is outside the range of reportable Doppler shiftsindicated by the configuration message, the device may report an invalidmeasurement result. Alternatively, if the device is unable to completethe Doppler measurements and transmit the Doppler measurement reportquickly enough (e.g., if it is unable to complete this process within atime specified by the configuration message), the device may report aninvalid measurement result.

In some embodiments, the Doppler measurement report is transmittedaccording to aperiodic timing with low latency. In these embodiments,the Doppler measurement report may be provided with an acknowledgmentmessage. The device may allocate all available CSI processing units topreparing and providing the Doppler measurement report when the Dopplermeasurement report is to be transmitted with aperiodic timing with lowlatency.

FIG. 7 describes a method for a device to autonomously perform Dopplermeasurement reporting without receiving a configuration message from abase station before performing the Doppler measurements and reporting.It may be understood that any applicable embodiment (i.e., anyembodiment that does not include a configuration message) describedabove in reference to FIG. 6 may be likewise implemented in the methodsdescribed in reference to FIG. 7 . For simplicity, these embodimentswill not be described again in the description of FIG. 7 .

In various embodiments, some of the elements of the methods shown may beperformed concurrently, in a different order than shown, may besubstituted for by other method elements, or may be omitted. Additionalmethod elements may also be performed as desired. As shown, the methodof FIG. 7 may operate as follows.

At 702, Doppler measurements are performed. The Doppler measurements mayinclude one or more first Doppler measurements on a first base stationand/or one or more second Doppler measurements on a second base station.The device may autonomously determine to perform the Dopplermeasurements and transmit the Doppler measurement report(s).

In some embodiments, the device may determine that the one or more firstDoppler measurements have changed compared to previous Dopplermeasurements on the first base station by more than a predeterminedthreshold amount. The device may periodically perform Dopplermeasurements on connected base stations to determine when the Dopplershift has changed by more than the predetermined threshold amount. Thepredetermined threshold amount may be selected such that a messagereceived with the predetermined threshold amount of uncompensatedDoppler shift may be difficult to successfully receive and/or decode bythe device. In these embodiments, the device may transmit the Dopplermeasurement report to the first base station responsive to thedetermination that the one or more first Doppler measurements havechanged compared to the previous Doppler measurements by more than thepredetermined threshold amount.

At 704, the Doppler measurement report is transmitted to the first basestation. The Doppler measurement report is based on the one or morefirst Doppler measurements and/or second Doppler measurements. TheDoppler measurement report may be used by the first and/or second basestations to perform pre-compensation of their respective Doppler shifts,as shown in FIG. 5 , so that the device receives signals from the basestations without a Doppler shift (or with a substantially reducedDoppler shift). For example, the device may receive communications fromthe first and/or second base stations that have been Dopplerpre-compensated based on the Doppler measurement report. The Dopplermeasurement report may individually report Doppler shifts of the firstand second base stations, or it may report a differential between theDoppler shifts of the first and second base stations.

In some embodiments, subsequent to transmitting the Doppler measurementreport, the device may refrain from transmitting subsequent Dopplermeasurement reports to the base station until expiration of a prohibitperiod. For example, the network may inform the device of a prohibitperiod, whereby the device will not transmit a second Dopplermeasurement report to the base station within the prohibit period aftertransmitting the first Doppler measurement report.

In some embodiments, the device may transmit a scheduling requestmessage to the base station on a physical uplink control channel (PUCCH)and receive an uplink grant from the base station. In these embodiments,the Doppler measurement report may be transmitted according to theuplink grant.

In some embodiments, the Doppler measurement report is transmittedwithin a media access control-control element (MAC-CE) message. TheMAC-CE message may further include a serving cell ID of the serving cellin which the Doppler shift is measured and/or a base station ID of thebase station whose Doppler shift is measured, in addition to theabsolute or differential quantized Doppler shift measurement. The basestation ID may be a logic ID such as a CSI-ReportConfigId or aNZP-CSI-RS-ResourceSetId, in which trs-info may be configured.

FIGS. 8-11—Additional Supporting Material

FIGS. 8-11 provide additional supporting material to describe details ofembodiments described herein.

In some embodiments, a CSI-ReportConfig message may be transmitted by abase station to a device to configure parameters for Doppler measurementreporting by the device. The CSI-ReportConfig message may set itsreportQuantity field to a value other than ‘none’ to indicate that thedevice is to provide Doppler measurement reporting using a channelmeasurement resource (CMR). The CMR may be configured using a trackingreference signal-information (trs-Info) field, which may configure anon-zero power (NZP) CSI-resource set (CSI-RS) as the CMR using theCSI-ReportConfig message. In various embodiments, configuring Dopplermeasurement reporting may be performed for aperiodic tracking referencesignals (AP-TRS), periodic tracking reference signals (P-TRS), orsemi-persistent tracking reference signals (SP-TRS).

The timeRestrictionForChannelMeasurements field in the CSI-ReportConfigmessage may be used to instruct the device to perform multiple Dopplershift measurements on the base station and report the average overmultiple measurements. In some embodiments, the CSI-ReportConfig messagemay configure the device to reserve two resource sets (i.e., two sets oftime and frequency resources) for Doppler measurement reporting to twodifferent base stations (e.g., a receding base station and anapproaching base station as shown in FIG. 5 ). FIG. 8 illustrates anexample message format, where the resourcesForChannelMeasurement fieldmay be used to indicate the resource set(s) to be used for Dopplermeasurement reporting for each of one or more base stations.

In some embodiments, as shown in FIG. 9 , theCSI-AssociatedReportConfigInfo field may be used to reserve one or moreresource sets for Doppler measurement reporting for one or morerespective base stations. The resourceSet field may be used to designatethe reserved resource set(s). In some embodiments, an interferencemeasurement resource (IMR), which may be a zero power IMR (e.g., CSI-IM)or a non-zero power IMR (e.g., NZP-CSI-RS) may not be configured forperforming Doppler measurement reporting.

In some embodiments, the reportQuantity field shown in FIG. 10 may beused to instruct the reporting device on how to report the Dopplermeasurements. For example, the reportQuantity field may be used tospecify whether the reporting device should report absolute Dopplershift measurements for one or more base stations, or differentialDoppler shift measurements between two or more base stations. Two setsof TRS may be configured as CMRs in the corresponding CSI-ReportConfigmessage, where each set of TRS corresponds to one base station.

The reportQuantity field may further specify reporting parameters forthe Doppler measurements. For example, it may specify that the reportingdevice is to report the sign (i.e., + or −) of the Doppler measurement.It may also specify the minimum and maximum reportable Doppler shift(e.g., 0 Hz to 8000 Hz, or another range) and the quantization step size(e.g., 100 Hz). For example, the reportQuantity field may inform thereporting device that it is allowed to report Doppler shifts up to themaximum reportable value, and that it should report Doppler shifts inincrements of the quantization step size. The reportQuantity field mayfurther specify that the UE may report an invalid entry in its Dopplermeasurement report, e.g., when the reporting value is out of range(e.g., is larger than the maximum reportable value) or when thereporting device has insufficient processing power to complete theDoppler measurement and provide the report within a designated latency.

In some embodiments, computational resources for a reporting device maybe counted in terms of CSI processing units. A device may have a certainavailable computational capacity to process a limited number ofsimultaneous Doppler measurement reports (e.g., if it receivesCSI-ReportConfig instructions from multiple base stations). Thereporting device may count each received CSI-ReportConfig message asreserving a fixed number of CSI processing units, e.g., 1 or 2, forperforming Doppler measurements and reporting. Alternatively, the CSIprocessing units per each CSI-ReportConfig message may be variable,e.g., it may vary depending on the parameters of the respectiveCSI-ReportConfig message. For example, the number of CSI processingunits associated with a CSI-ReportConfig message may be proportional tothe number of resource sets reservations specified in theCSI-ReportConfig message. The rule for counting CSI processing units maybe established according to a cellular telecommunication standard, or itmay be reported by a UE as UE capability information.

A reporting device may be configured to accept and processCSI-ReportConfig messages until its maximum number of CSI processingunits have been allocated, upon which the device may provide an invalidDoppler measurement report in response to any subsequentCSI-ReportConfig messages to indicate that the device currently hasinsufficient processing bandwidth to produce and provide additionalDoppler measurements.

FIGS. 11A and 11B are tables illustrating two potential sets of timingparameters for aperiodic CSI transmission. In FIGS. 11A and 11B, Z isthe minimum timing offset between the last symbol of the physicaldownlink control channel (PDCCH) message triggering the CSI report(i.e., CSI-ReportConfig message) and the first uplink symbol to carrythe corresponding CSI report(s), including the effect of the timingadvance. Z′ is the minimum timing offset between the last symbol of thelast reference signal used for measurement and the first uplink symbolto carry the corresponding CSI report(s), including the effect of thetiming advance. Table 11A illustrates a lower latency set of Z and Z′,whereas Table 11B illustrates a higher latency set of Z and Z′. Thevariable μ is an index representing different subcarriers. The reportingUE may use a lower latency set of Z and Z′ in certain scenarios. Forexample, a low latency set of minimum timing offsets may be used whenthe CSI Doppler measurement report is triggered through a transportblock or is provided within a hybrid automatic repeat requestacknowledgment (HARQ-ACK) message rather than being transmitted within aphysical uplink shared channel (PUSCH). Alternatively or additionally, areporting device may elect to use the low latency set of timing offsetswhen it is currently preparing a CSI Doppler measurement report for onlya single base station. In these embodiments, the reporting device mayallocate all of its CSI processing units to providing the Dopplermeasurement report, to facilitate satisfying the lower latency minimumtiming offsets.

Still another exemplary embodiment may include a method, comprising: bya device: performing any or all parts of the preceding examples.

Still another exemplary embodiment may include a method, comprising: bya base station: performing any or all parts of the preceding examples.

A further exemplary embodiment may include a device, comprising: anantenna; a radio coupled to the antenna; and a processing elementoperably coupled to the radio, wherein the device is configured toimplement any or all parts of the preceding examples.

Another exemplary embodiment may include an apparatus, comprising aprocessor configured to implement any or all parts of the precedingexamples.

Yet another exemplary set of embodiments may include a non-transitorycomputer accessible memory medium comprising program instructions which,when executed at a device, cause the device to implement any or allparts of any of the preceding examples.

A still further exemplary set of embodiments may include a computerprogram comprising instructions for performing any or all parts of anyof the preceding examples.

A yet further exemplary set of embodiments may include an apparatuscomprising means for performing any or all of the elements of any of thepreceding examples.

It is well understood that the use of personally identifiableinformation should follow privacy policies and practices that aregenerally recognized as meeting or exceeding industry or governmentalrequirements for maintaining the privacy of users. In particular,personally identifiable information data should be managed and handledso as to minimize risks of unintentional or unauthorized access or use,and the nature of authorized use should be clearly indicated to users.

Embodiments of the present invention may be realized in any of variousforms. For example, in some embodiments, the present invention may berealized as a computer-implemented method, a computer-readable memorymedium, or a computer system. In other embodiments, the presentinvention may be realized using one or more custom-designed hardwaredevices such as ASICs. In other embodiments, the present invention maybe realized using one or more programmable hardware elements such asFPGAs.

In some embodiments, a non-transitory computer-readable memory medium(e.g., a non-transitory memory element) may be configured so that itstores program instructions and/or data, where the program instructions,if executed by a computer system, cause the computer system to perform amethod, e.g., any of a method embodiments described herein, or, anycombination of the method embodiments described herein, or, any subsetof any of the method embodiments described herein, or, any combinationof such subsets.

In some embodiments, a device (e.g., a UE) may be configured to includea processor (or a set of processors) and a memory medium (or memoryelement), where the memory medium stores program instructions, where theprocessor is configured to read and execute the program instructionsfrom the memory medium, where the program instructions are executable toimplement any of the various method embodiments described herein (or,any combination of the method embodiments described herein, or, anysubset of any of the method embodiments described herein, or, anycombination of such subsets). The device may be realized in any ofvarious forms.

Although the embodiments above have been described in considerabledetail, numerous variations and modifications will become apparent tothose skilled in the art once the above disclosure is fully appreciated.It is intended that the following claims be interpreted to embrace allsuch variations and modifications.

1. A device, comprising: a radio operably coupled to an antenna; and aprocessor operably coupled to the radio, wherein the device isconfigured to: receive a configuration message from a first basestation, wherein the configuration message specifies one or moreparameters of a Doppler measurement report; perform one or more firstDoppler measurements on the first base station; and transmit the Dopplermeasurement report to the first base station, wherein the Dopplermeasurement report is based on the one or more first Dopplermeasurements and the one or more parameters.
 2. The device of claim 1,wherein the one or more first Doppler measurements are performedresponsive to receiving the configuration message.
 3. The device ofclaim 1, wherein the one or more parameters comprise an instruction toperform a plurality of first Doppler measurements, wherein performingthe one or more first Doppler measurements comprises performing theplurality of first Doppler measurements, and wherein the Dopplermeasurement report is based on an average of the plurality of firstDoppler measurements.
 4. The device of claim 1, wherein the wirelessdevice is further configured to: perform one or more second Dopplermeasurements on a second base station, wherein the Doppler measurementreport is further based on the one or more second Doppler measurements.5. The device of claim 4, wherein the Doppler measurement reportcomprises a differential of the first and second Doppler measurements.6. The device of claim 1, wherein the one or more parameters comprise aspecification of one or both of: one or more time and frequencyresources for performing the one or more first Doppler measurements; andone or more time and frequency resources for transmitting the Dopplermeasurement report.
 7. The device of claim 1, wherein the Dopplermeasurement report specifies that the Doppler measurement report isinvalid.
 8. The device of claim 1, wherein the one or more parameterscomprise: a minimum absolute reportable Doppler shift; a maximumabsolute reportable Doppler shift; and a quantization step size.
 9. Thedevice of claim 1, wherein the Doppler measurement report is providedaccording to aperiodic timing with low latency, and wherein the Dopplermeasurement report is provided with an acknowledgment message.
 10. Thedevice of claim 1, wherein the device comprises a cellular transceiverinstalled on a high-speed train.
 11. The device of claim 1, wherein theconfiguration message comprises a channel state information(CSI)-ReportConfig message, and wherein the Doppler measurement reportis comprised within a CSI transmission.
 12. A non-transitorycomputer-readable memory medium comprising program instructions which,when executed by a processor, cause a first base station to: transmit aconfiguration message to a device, wherein the configuration messageinstructs the device to perform one or more first Doppler measurementson the first base station and specifies one or more parameters of aDoppler measurement report; receive the Doppler measurement report fromthe device, wherein the Doppler measurement report is based on the oneor more parameters and results of the one or more first Dopplermeasurements; and transmit communications to the device with Dopplerpre-compensation, wherein the Doppler pre-compensation is based on theDoppler measurement report.
 13. The non-transitory computer-readablememory medium of claim 12, wherein the one or more parameters comprisean instruction to perform a plurality of first Doppler measurements, andwherein the Doppler measurement report is based on an average of theplurality of first Doppler measurements.
 14. The non-transitorycomputer-readable memory medium of claim 12, wherein the configurationmessage further instructs the device to perform one or more secondDoppler measurements on a second base station, wherein the Dopplermeasurement report is further based on the one or more second Dopplermeasurements, wherein the Doppler measurement report comprises adifferential of the first and second Doppler measurements, and whereinthe communications transmitted to the device are Doppler pre-compensatedwith half or all of the differential of the first and second Dopplermeasurements.
 15. A method, comprising: performing one or more firstDoppler measurements on a first base station; transmitting the Dopplermeasurement report to the first base station, wherein the Dopplermeasurement report is based on the one or more first Dopplermeasurements; and receiving communications from the first base station,wherein the communications are Doppler pre-compensated by the first basestation based on the Doppler measurement report.
 16. The method of claim15, the method further comprising: determining that the one or morefirst Doppler measurements have changed compared to previous Dopplermeasurements on the first base station by more than a predeterminedthreshold amount, wherein transmitting the Doppler measurement report isperformed responsive to the determination that the one or more firstDoppler measurements have changed compared to the previous Dopplermeasurements by more than the predetermined threshold amount.
 17. Themethod of claim 15, the method further comprising: subsequent totransmitting the Doppler measurement report, refraining fromtransmitting subsequent Doppler measurement reports to the base stationuntil expiration of a prohibit period.
 18. The method of claim 15, themethod further comprising: transmitting a scheduling request message tothe base station on a physical uplink control channel (PUCCH); andreceiving a PUCCH resource configuration or uplink grant from the basestation, wherein the Doppler measurement report is transmitted accordingto the PUCCH resource configuration or uplink grant.
 19. The method ofclaim 15, the method further comprising: receiving an uplink grant fromthe base station, wherein the Doppler measurement report is transmittedwithin a media access control-control element (MAC-CE) message, andwherein the Doppler measurement report is transmitted according to theuplink grant.
 20. The method of claim 15, the method further comprising:performing one or more second Doppler measurements on a second basestation, wherein the Doppler measurement report is further based on theone or more second Doppler measurements, and wherein the Dopplermeasurement report comprises a differential of the first and secondDoppler measurements.